Popis: |
The seasonal biomass and resource allocation patterns of a perennial geophytic species, Haemanthus pubescens subspecies pubescens, were investigated. Four phenophases for the species were identified and the annual patterns of dry mass and resource allocation were identified from individuals sampled from natural populations. From the results, four general resource allocation patterns were identified: (1) mobile macronutrients (N, P and K) and Cu; (2) immobile macronutrients (Mg and Ca) and Mn; (3) soluble carbohydrates, starch, Zn and Fe; and (4) Na, all with their own distinctive allocation patterns. This study confirms distinct allocation patterns between the resources and biomass. Furthermore, it was found that environmental constraints contributed towards the differential seasonal allocation patterns of the resources and biomass. The development of an underground storage organ is regarded as an evolutionary mechanism to cope with soils of a low nutrient status, characteristic of the Cape fynbos, and as a strategy for the protection of dry matter and resources against seasonal periodic droughts and fires. |